(v17preprint37)Galvanic Corrosion between Carbon Steel and CuAlBe: Experimental Design with Anodic Dissolution Current as the Dependent Variable

摘要

Galvanic corrosion between carbon steel and the shape-memory alloy CuAlBe was investigated. A fractional factorial design of 26-2 including 6 central points was used with the following variables: Cl-, SO42-, S2-, HCO3-, ratio of anodic to cathodic area (1:1, 1:0.5, 1:0.25) and temperature (25, 35 and 45 °C). The experimental design was used to investigate the main factors influencing the anodic dissolution current (dependent variable) as calculated from the galvanic current density. The dependent variable was directly proportional to the cathodic area, even in complex electrolyte solutions such as the water produced in mature oil wells. The experimental design provided information that could be used to minimize the dissolution of carbon steel. An analysis of the response surfaces showed that the area, [SO_4~(2-)] and [HCO_3~-], and the SO_4~(2-) - HCO_3~- interaction significantly (p<0.1) influenced the anodic dissolution current. The relationship between the cathodic and anodic areas had the largest influence on the anodic dissolution current.